Method for etching the surface of aluminum fragments, aluminum fragments with an etched surface and material composites containing such fragments

Patent metadata

Field	Value
Publication number	US-11085117-B2
Application number	US-201716077436-A
Country	US
Kind code	B2
Filing date	Jan 9, 2017
Priority date	Feb 11, 2016
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

A method for etching fragments of aluminum or an aluminum alloy comprising the steps of: a. providing a hydrochloric acid solution in a trough-shaped container; b. inoculating the hydrochloric acid solution by chemically dissolving an amount of aluminum to produce an etching solution; c. adding the fragments to the etching solution immediately after the inoculation; d. etching the fragments for 0.5 to 10 minutes while stirring in such a way that the fragments are entrained by the motion of the etching solution; e. stopping the etching by diluting the etching solution with water; f. removing the etched fragments; g. repeatedly rinsing the fragments with water and h. rinsing the fragments with an organic desiccant. An etched fragment of aluminum or an aluminum alloy and also to a composite material comprising etched fragments.

First claim

The invention claimed is:

1. An aluminum or aluminum alloy fragment etching method comprising the steps of:
a. providing a hydrochloric acid solution having a concentration of 1.1 to 4.2 moles HCl per liter of water in a trough- or vat-shaped container;
b. inoculating the hydrochloric acid solution by chemically dissolving a quantity of aluminum from the interval 0.5 g to 17.5 g per liter to produce an etching solution;
c. adding aluminum or aluminum alloy fragments to the etching solution immediately after the inoculation;
d. etching the aluminum or aluminum alloy fragments for 0.5 to 10 minutes while circulating the etching solution with the fragments such that the fragments are entrained by the movement of the etching solution to produce etched aluminum or aluminum alloy fragments;
e. stopping the etching within a few seconds by diluting the etching solution with water;
f. removing the etched aluminum or aluminum alloy fragments from the etching solution;
g. repeatedly rinsing of etched aluminum or aluminum alloy fragments with water immediately after the removal and
h. rinsing the etched aluminum or aluminum alloy fragments with an organic desiccant.

2. The etching method according to claim 1 , wherein the hydrochloric acid solution has a concentration of 1.7 to 2.5 mol of HCl per liter of water.

3. The etching method according to claim 1 , wherein the hydrochloric acid solution has a concentration of 2.1 mol of HCl per liter of water.

4. The etching method according to claim 1 , further comprising seeding the hydrochloric acid solution by chemically dissolving 2 to 2.5 g of aluminum per liter.

5. The etching method according to claim 1 , wherein the aluminum or aluminum alloy fragments are etched while circulating the etching solution with the aluminum or aluminum alloy fragments for 4 to 5 minutes.

6. An etched fragment made of aluminum or an aluminum alloy produced by the method according to claim 1 , wherein the surface of the etched aluminum or aluminum alloy fragment has anchoring structures, wherein the shape of the fragment corresponds to its shape before the etching, wherein the fragment is a wire having a wire diameter of at least 50 micrometers and a length of at least 0.5 millimeter.

7. The etched aluminum or aluminum alloy fragment according to claim 6 , wherein the etched aluminum or aluminum alloy fragment is a tetrapod.

Assignees

• Univ Kiel Christian Albrechts

Inventors

• Baytekin-Gerngross Melike
• Gerngross Mark-Daniel
• Carstensen Juergen
• Adelung Rainer

Classifications

• C08K3/08

  Metals · CPC title

• H01B1/023

  Alloys based on aluminium · CPC title

• C23F1/20 Primary

  for etching aluminium or alloys thereof · CPC title

• C09C1/64

  Aluminium · CPC title

• C08K2003/0812

  Aluminium · CPC title